This invention relates to powered hydraulic steering systems and, in particular, to power assist hydraulic steering systems typically used for marine craft.
Published International Patent Application PCT/JP 00/04573 to Marol discloses a power steering system including a closed hydraulic circuit with a helm pump and a double acting hydraulic cylinder connected to the rudder. The powered hydraulic pump is activated by sensing pressure output from the helm pump.
One problem with such a power steering system is that the pump is only activated after a predetermined amount of pressure builds up from the operation of the helm pump. This causes a lack of sensitivity when the operator steers the vessel via the helm.